252 



the rest. The plates need not exceed in size the pencil of 

 rays, and may be very small. 



" If this succeed, we might gain great advantages by thus 

 mapping the stars and nebulae, and examining their state at 

 our leisure, in our study, and being able to take advantage 

 of what every practical astronomer knows to occur so seldom 

 in our climate, namely, a state of the atmosphere favourable 

 for delicate observation. 



" To try it, some easily divided stai*, such as Z, Ursae, 

 might be first used, and, if the plate registered it as a double 

 star, we might then proceed to other more difficult objects." 



DONATIONS. 



A Letter on the State of Schools of Chemistry in the United 

 Kingdom. By Wm. Gregory, M. D., M. R. I. A., &c. &c. 

 Presented by the Author. 



A volume of Tracts relating to the Historical Society of 

 Dublin. Presented by G. A. Kennedy, M. D., M. R. I. A. 

 &c. &c. 



Journal of the Franklin Institute. Third Series. Vol. II. 



Eleventh Report of the British Association for 1841. 

 {Plymouth). Presented by the Association. 



Account of the Magnetical Observatory of Dublin. By 

 the Rev. H. Lloyd, D. D., &c. Presented by the Author. 



A View of the Coinage of the Heptarchy. By John Lind- 

 say, Esq. Presented by the Author. 



Memoires de la Societe Geologique de France. Tome IV. 

 Second Part. 



Transactions of the Royal Society of Copenhagen. Vol. VI. 

 (1841). 



On the Use and Study of History. By W. Torrens M'Cul- 

 lagh, LL. B. Presented by the Author. 



